package 华为机试.求解立方根;

import java.util.Scanner;

public class Main
{
    public static void main(String[] args)
    {
        Scanner sc=new Scanner(System.in);
        while(sc.hasNext())
        {
            double input=sc.nextDouble();
            double result=getCubeRoot(input);
            System.out.printf("%.1f\n", result);
        }
        sc.close();
    }
    public static double getCubeRoot(double input)
    {
        double min=0;
        double mid=0;
        double max=input;
        while((max-min)>0.001)
        {
            mid=(min+max)/2;
            if(mid*mid*mid>input)
            {
                max=mid;
            }
            else if(mid*mid*mid<input)
            {
                min=mid;

            }
            else
            {
                return mid;
            }
        }
        return max;
    }
}
